Network rank is a quantification of the quality of a node's connection to a root node. A node's network rank may be advertised to its neighbors and used by the neighbors to evaluate the node as a potential parent. A node's rank is based on the number of hops required to reach the root node and other factors, such as the quality of the links between nodes.
When a node's advertised rank fluctuates in real time, a network may become unstable. Brief aberrations in network quality may cause a node to select a parent based on aberrant data or may impact its advertised rank. Frequent changes in advertised rank may cause nodes to frequently change parents which may lead to instability in the network.
It is desirable to have a system that incorporates gradual changes to the rank advertised by a node. Such a system would minimize the impact of temporary fluctuations in rank to provide for greater network stability, while still being responsive to persistent changes in rank.